The invention relates to the field of firearms and, more particularly, to a shell for cleaning the bore of a firearm.
The discharge of conventional firearms results in deposits of residue on the inside surface of the bore of the firearm. Such deposits, over time, can damage the firearm, impair its performance, and lead to potentially dangerous conditions.
The cleaning of the bore of a firearm by conventional means is a tedious process wherein cleaning wads attached to rods are doused with cleaning solution and run through the bore. Such conventional cleaning is not conveniently effected during hunting trips or tournaments, because of the time involved and the extra hardware which must be carried by the operator of the firearm.
Numerous devices have been developed to attempt to simplify the cleaning of the bore of firearms. Examples of such devices are disclosed in U.S. Pat. Nos. 4,998,368, 4,328,632, 3,740,883 and 3,476,047.
U.S. Pat. No. 4,328,632 to Beers discloses an apparatus for cleaning firearms which has a cartridge of pressurized gas having a puncturable cap. The cartridge is disposed in the firearm with the cap facing the firing pin. Operation of the firing pin is said to puncture the cap causing the thus released pressurized gas to propel the cartridge through the bore of the gun. Cleaning materials are disposed in the bore ahead of the cartridge and are pushed through the bore by the cartridge. However, such a device, when used, results in the cartridge becoming a potentially hazardous projectile. Further, the cartridge must contain gas sufficiently pressurized so as to propel the entire cartridge through the bore of the firearm. The cap of the cartridge must be of sufficient thickness to contain this pressure, which may interfere with the required puncturing of the cap by the firing pin. Further, the firing pin of modern firearms is generally too small to form a large enough puncture in the cap. With these numerous complications, it is apparent that the cartridge could easily become jammed in the bore of the firearm. Finally, such a device may not be suitable for larger caliber guns or firearms where the size and required pressure of the cartridge would become impractical.
U.S. Pat. No. 4,998,368, to Blase, discloses a cleaning device including a compressed gas cartridge disposed in the firing chamber of the firearm and having a cleaning wad releasably disposed at the end of the tank. A cap of the tank is punctured by the firing pin of the firearm, to release the compressed gas and flush the cleaning wad through the bore. This device is said to overcome disadvantages inherent in the other mentioned patents such as the potentially hazardous discharge of heavy elements of the cleaning device from the bore of the firearm (see, for example, U.S. Pat. No. 4,328,632 to Beers).
Blase '368, however, also has drawbacks. The orientation of the cartridge to align the cap of the cartridge with the firing pin results in an acceleration of the cartridge towards the bore. It is said, in Blase, that the cartridge is held in place by a flange at the base of the cartridge and by a restriction in diameter of the gun bore. It appears, however, that special structure would be required to grip the flange, and that a conventional firearm, without such special structure, would have to rely on the reduction in diameter of the bore to restrain the cartridge. This, however, is likely to lead to damage to the bore from impact with the cartridge.
Furthermore, in Blase the compressed gas flows around the cartridge to the bore. This flow may be significantly interfered with due to the small flow space between the cartridge and the cartridge chamber. The flow may be further interfered with by the tendency for the cartridge to press against or seat against the reduction in diameter of the bore, thus serving as a valve to throttle or totally block flow.
Finally, in Blase, the firing pin hits against a pin in the apparatus which transmits the force of the pin to the cap to puncture the cap. In order to properly transmit this force, the intermediate pin must be of a hard metal, rather than the soft material typical of conventional primers. Impact of the firing pin with the hard metal intermediate pin over continued use would lead to excessive wear and/or damage to the firing pin.
It is clear that the need still exists for a device for cleaning the bore of a firearm which is effective to clean the bore of the firearm, and convenient to use, which does not involve the discharge of potentially dangerous projectiles from the firearm, and which does not require modification to the firearm or cause damage to the bore of the firearm to be cleaned.
It is therefore the principal object of the invention to provide an apparatus which is effective, convenient, and safe for use in cleaning the bore of a firearm.
It is a further object of the invention to provide such an apparatus, the use of which does not require modification of the firearm or special equipment.
It is a still further object of the invention to provide such an apparatus which does not damage the bore of the firearm.
It is another object of the invention to provide such an apparatus which is similar in use to a conventional round of ammunition.
Other objects and advantages will appear hereinbelow.